fassier-duval

Definition

Anterolateral bowing

True bone dysplasia

- hamartomatous area in the tibia

- non union or potential non union through pathological fracture in this region

The defect in the bone is filled with mature, fibrous connective tissue

- not really a pseudoarthrosis

- by definition, a pseudarthrosis has a cleft lined by fibrocartilage containing fluid and bounded by a capsule

Defect

Abnormality of type 1 collagen

- amino acid substitution of glycine with another amino acid

- prevents triple helix formation

Many many deformities described

- some 286 mutations of Type 1 collagen described

Sillence Classification

There are actually now 7 

Type I

- mild

- AD

- blue sclera